Blind stitch sewing machine



May 31, 1932. c. w. MUELLER 1,

BLIND STITCH SEWING MACHINE I Filed Sept. 21, 1929 3 Sheets-Sheet 1 3nnentor,

' (Ittorneg y 1932 c. w. MUELLER BLIND STITCH SEWING MACHINE Filed Sept. 21, 1929 s Sheets-Sheet 2 HIIHIIIIIIHIIHIIIIH y 1932- c. w. MUELLER 1,860,902

BLIND STITCH SEWING MACHINE Filed Spt. 21, 1929 5 Sheets-Sheet 3' W 3nventor,

(Ittonfeg Patented May 31, 1932 warren stares Fas enercreme CHARLES w. MUELLER, or L'OUIS, Mrsseunr, essienoit T0 LEWIS LINVISIIBLE STITCH 'MACHINE COMPANY, or s'r. Louis, MIssoi'mI, A CORIORA'IION or MAINE BLIND STITCH SEWING MACHINE Application filed September 21, 1929. Serial No. 394,230.

This invention relates to new and useful improvements in blind stitch sewing machines of that type which are especially adapted for staying Operations on fur coats, although the invention is adapted for use in connection with other sewing operations.

This invention embodies improvements on the construction shown in my Patent 1,739,081, Dec. 10, 1929.

In performing a staying operation on a fur coat, the hair side isthe under side and consequently the flesh side is the upper side. In some of these skins there are spots which are either without any hair or are with a very small portion of hair, and still in other places the hair is very heavy thusforining a very uneven or wavy under surface to the skin. In the machine shown. in my patent abovereferred to, the ridge forming disc is not yieldably supported for vertical movements and consequently it this construction was employed in staying operations on fur coats, the depth of needle penetration would vary depending on the varied amount or thickness of the hair on the under side of the skin.

It is, therefore, the principal object of this invention to provide a vertically adjustable fixed stop disposed above the disc and to provide the roller on which the disc bears with a yieldable support which tends to urge the disc upwardly toward the fixed stop whereby the flesh sideiof the skinor work will be retained in a fixed position relative to the needle penetration and a uniform depth of needle penetration will be maintained, the vertically yieldable' disc serving to automatically position itse f relative to the wavy under side of the skin which, as above an ineffective or nOnbp'erating position because the use of this top stop is unnece ssary owing to the fact that the material or work is heavy and is of uniform thickness. Furthe disc is entirely taken up,because the uni i'ormity of thickness of the work renders un- W necessary and undesirable the employment of a vertically yieldable disc.

Therefore, anotherobject of-the' invention lies in thepro ision of means for taking up the yieldable support for the disc supporting roller whereby the present'invention', when the adjustable stop is elevated above the work, may be employed for otherb'lind stitch operations wherein the work is of uniform thickness. 7

It has been found in practice, when-the machine was being used for stitching work having'heavy cross seams, that the-disc would move upwardly into the path of the needle and break the same. This condition was brought about immediately following the heavy seam being fed past the needle. During the time the seam was directly under the path of needle penetration, the seam, acting as a resistance, caused the work arm to-' gether with the disc to be lowered a distance substantially equal to the thickness of the seam. Thus immediately after the seam was fed past the needle, but while the work arm was still in its lowered pos'itiomthe resistance to the upward movement of the disc which floats on its supportingroller was removed and consequently the disowould be bodily moved or projected upwardly away from its supporting rollerand into" the path of the needle, as the body fabric" immediately in front of the seam would not otter the necessary resistance to said upward bodily movej ment of the disc.

Therefore, another object of my invention is to provide an adjustable stop which c0- operates with the pivoted work arm to limit the upward movement of the disc relative to by following the description, the appended driving connection claims, and the several views illustrated in the accompanying drawings.

Inthe drawings:

Figure '1 is an elevation of the left hand 7 side of a sewing machine embodying my invention, Figure 2 is a top plan view thereof, Figure 3 is a front elevation thereof, Figure 1 is a vertical sectional View taken on the line 41- 1 of Figure 3, V Figure 5 is a vertical sectional view taken on the line 55 of Figure 1, V

Figure 6 is aplan View of the presser foot, fixed upper stop, ridge-forming disc, topfeed, needle, and looper, in cooperative relation, V V V Figure 7 is a perspective View of the discsupporting roller and arm on which the roller is mounted, and

Figure 8 is a perspective View showing the between the rock shaft and'the disc. 1

Like reference numerals designatecorrespending parts throughout the several figures of the drawings;

Referring to the accompanying drawmgs,

my improved sewing machine includes a 3Q yieldingly held in operative position by a spring 8a. The work support 8 is provided at its left rear corner with a reduced extension 10 whichprojectstoward and under a presser foot 11 which is rigidly secured to the forward end of the overhanging arm 6.

Formed in the presser footll is a slot 12 having its longitudinal axis extending parallel to a rock shaft 13 which is journaled in the overhanging arm 6. Fixed to an arm 3 secured to the rock shaft 13 is a needle 14 which has its path of oscillation across the.

slot 12 of the presser foot, and cooperating with the needle to form a series of single thread chain stitches is a looper 15, said ...looper being operated from the rock shaft 13 by a connection shown in my patent referred to above.

Journaled on the under side of the work support 8 and extension 10 thereof, and lo- ,cated in rear ofandin spacedrela'tion to the axis 9 of said work support, is a rock shaft 16. The rock shaft 16 is oscillated from the main shaft'by the mechanism shown in my patent referred'to above, the left handend of the rock shaft being journaled in a 2 lug 17 which depends from the extension 10. Pivot-ed to the left hand face or end of the work arm extension 10 as at 18 is one end of a roller supporting arm 19. A roller 20 is journaled on the arm 19 at a point adjacent the free end thereof through the medium of a bearing arm 21 and a pivot pin 22.

Supported by the roller 20 is a ridgeforming disc 23. The axis of the roller 20. 'is directly below and in the same vertical plane in which the needle reciprocates. The disc 23 is preferably cut-away as at 24, 24 to form two quadrant shaped sections 25 and 26 respectively, the former constituting a ridge forming and work feeding section and the latter forming a supporting section. The disc 23 is formed with an axial bore having a pivot pin 27 journaled therein. The ridgeforming section 25 of the disc is formed with V a concentric periphery 28 having a tooth 29 formed at its feeding end. The supporting section 26 of said disc is provided with a peripheral cam comprisingtwo spaced concentric portions 30 and 31 of different radii, and a connecting eccentric portion 32. The cam thus formed has rolling contact with the roller 20. The ridge forming section 25 of the disc is disposed in alinement with the slot 12 of the presser foot 11 and is adapted to project a ridge or node of material upwardly into needle penetrating position, and

to feed the material rearwardly a stitchlength after the needle has withdrawn from the material. It is, therefore, desirable to maintain the axis 27 of the disc in the vertical plane containing the axis of the roller 20 and the path of needle reciprocation. To

this end, I have provided an arm 33 having one end fixed to the fulcrum pin 27 of the disc and the other end journaled on a hearing pin 34 fixed in the extension 10 of the work support and located in advance of the rock shaft 16. A coil spring 35 has its lower end connected to a pin 36 fixed to the outer end of the roller supporting arm 19 and its upper end fixed tothe disc supporting arm 33. Thus the spring 35 functions to yieldably retain the disc in engagement with the sup porting roller 20.

In order to yieldably support the roller 20 and thereby yieldably support the disc 23,

I have provided the lug 17, at a point below the arm 19, with a vertically disposed threaded socket 37 and have mounted in said socket upward movement of the roller supporting A:

iii)

arm 19 is limited by its engagementiwith shoulder or stop 41 formed on the lug 17, the spring 39 normally tending to yieldably retain the arm 19 against said stop. When,

, however, the pilot 40 is disposed below and to the supporting section 26 of thedisc 23.

Supported 011 the presser foot 11 for cooperation with the disc 23 is a vertically adjustable fixed stop whichI have indicated as a whole by the reference numeral 46. This stop includes a stop plate 47 which extends longitudinally of the presser foot, the front end of the plate 47 being pivoted on a horizontal axis 48 attached to the front end of the presser foot in front of th-e'slot 12 and the rear or free end of the plate projecting into the slot'12 "and terminating directly above the disc 23 and immediately in front of the path of needle travel. A vertically disposed screw 49 is fixed to and extends upwardly from the presser foot 11 at a point directly in front of the slot 12. This screw projects upwardly through an opening formed in the stop plate 47 and a nut 51 which constitutes a stop to limit the upward movement of the plate 47 is threaded onto the screw 49. The nut 51 is provided with a knurled edge 52 and a spring finger 53 which is fixed to the foot, cooperates with said knurled edge to retain the stop 46 in any position of vertical adjustment.

Cooperating with the under surface of the presser foot 11 is a clamp which includes spaced clamping arms 54 and 55 betweenv which the ridge forming section 25 of the disc 23 projects. The clamp arms are pivoted to arms 56, 56 of supporting levers having hubs 57 which are mounted on the bearing pin 34 on opposite sides of the disc supporting arm 33. Each of the levers includes a downwardly extending arm 58 and to the lower end of each arm is connected one end of a coil spring 59, the other end of the spring being connected to a pin 60 which is fixed to the lug 17. By means of the springs 59 the work clamp is held yieldingly against the presser foot 11, or when the work is positioned between the presser foot and the clamp, the latter will cooperate with the foot to clamp the work against the presser foot while the ridge is being formed in the material and while the needle is penetrating said ridge.

Cooperating with the work clamp in rear of the needle 14 is a top feed mechanism which under.

includes a feed dog 61, said f eed dog being operated from the rock shaft 13 by a mechanism shown in my patent referred to above.

In order to prevent the floating disc 23 from being projected upwardly away from its supporting roller 20, I have provided an adjustable stop to limit the free or upward movement of said disc. To this end, the disc supporting arm 33 is provided with a depending. arm 62 whichis positioned between 7 the downwardly extending arms 58, 58 of the work clamp. Threaded into the lower end of the. arm 62 is a stop screw 63 which is adapted to abut the outer face of the socket 37 when the disc is elevated by the coopera tion of the eccentric portion 32 and the roller 20 and thereby prevent further upward movement of the disc. A look nut 64 is associated with the screw to retain the latter in an adjusted position. I

In operation, assuming thatthe machine is to be used in staying operations on fur coats, the skin is placed between the presser foot 11 and the work clamp 54 with the hair side centric peripheral portion 30 of the supporting portion 26 of the disc is resting on and is in direct contact with the roller 20. The

In the Figure 4 position, the condisc therefore is in its higher position and has formed a ridge or node in the material.

The disc is then oscillated to the right, as

order to maintain uniform depth of needle penetration, the upper stop 46 is vertically.

adjusted to suit conditions, and the spring 39 functions to yieldably retain or urge the disc against the fixed upper stop. Thus any wavy or uneven under surface to the material. will be automaticallycompensated for by, the yieldably supported disc, and by reasonof the fixed stop 46 the needle will maintain uniform depth of penetration in the material;

If it is desired to employ this mechanism in blind stitching operations on materials of uniform thickness, such as padding operations, or pants bottom operations, the adjusting screw 38 is elevated until the pilot 40 engages the bearing arm 21, and the stop 46 is elevated by adjusting the nut 51 so that said stop will have no effect on the material.

When the machine is used for stitching work having heavy seams, the adjusting screw 38 is elevated to eliminate the yieldable support for the disc, and the top stop 46 is elevated to ineffective position. As previously stated, practice has shown that immediately after the seam passed beyond the As the disc is, again oscillated,

needle, the disc wouldbe thrust upwardly away from its supporting roller and be roller 20, whereby the disc will be prevented from being projected into the path of the needle. 7

It is of course to be understoodthat the details of structure and arrangements of parts may be variously changed and modified without departing from the spirit and scope Y of my invention.

I claim:

1. In a sewing machine, the combination of an oscillatory ridge-forming disc, a work support, and spring means for yieldably supporting said disc on said work support for bodily vertical movements.

2. In a sewing machine, the combination of-an oscillatory ridge-forming disc, a work support, means for yieldably supporting said 7 disc on said work support for bodily vertical movements, and a fixed stop disposed above and cooperating with said disc.

3. In a sewing machine, the combination of an oscillatory ridge-forming disc, a work support, means for yieldably supporting said disc on said work support for bodily vertical movements, and a vertically adjustable fixed stop disposed above and cooperating with said disc. 7

4:. In a sewing machine, the combination of an oscillatory ridge-forming disc, a work support, means for yieldably supporting said disc on said work support for bodily vertical movements, and means for varying the tension of said yieldable support.

5. In a sewing machine, the combination of an oscillatory ridge-forming disc, a work support, means for yieldably supporting said disc on said work support for bodily vertical movements, and means for changing said vertically yieldable support to a non-yieldof an oscillatory ridge-forming disc, a work support, means for yieldably supporting said disc on said work support for bodily vertical movements, and a fixed stop disposed above and cooperating with said disc, said stop 1. including a pivoted stop plate disposed above the disc, and a vertically adjustable stop disdisc on said work support for bodily vertical movements, the path of needle reciprocations being in a plane crossing the plane of the disc, and means including a rock shaft separate from the disc support for oscillating said disc. 1

9. In a sewing machine, the combination with a stitch forming mechanism; including a reciprocatory needle, of a slotted presser foot, a work support, a ridge-forming disc located in the plane of the slot of the presser foot, means for yieldably supporting said disc on said work support for bodily vertical movements, the path of needle reciprocations being in a plane crossing the plane of the disc, means including a rockshaft separate from the disc support for oscillating said disc, and means for changing the vertically yieldable support of the disc toa non-yieldable support. 5

10. In a sewing machine, thecombination with a stitching forming mechanism including a reciprocatory needle, of a slotted presser foo-t, a work support, a ridge-forming disc located in theplane of the slot of the presser foot, means for yieldably supporting said disc on said work support for bodily vertical movements, the path of needle reciprocations being in a plane crossing the plane of the the disc, means including a rock shaft separate from the disc support for oscillating said disc, and a fixed stop disposed above and cooperating with the disc to maintain uniform depths of needle penetration.

11. In a sewing machine, the combination with astitch forming mechanism including a reciprocatory needle, of a slotted presser foot, a work support, a rldge-forming disc located in the plane of the slot of the presser foot, means for yieldably supporting said disc on said work support for bodily vertical movements, the path of needle reciprocations being in a plane crossing the plane of the disc, means including a rock shaft sep arate from the disc support for oscillating said disc, and a vertically adjustable fixed stop disposed above and cooperating with the disc to maintain uniform depths of needle penetration.

12. In a sewing machine, the combination with a stitch forming mechanism including a Y reciprocatory needle, of a slotted presser foot, a work support, a ridge-formmg disc located in the plane of the slot of the presser foot, means for yieldably supporting said disc on said, work support for bodily vertical 7 movements, the path of needle reciprocations being in a plane crossing the plane of the disc, means including a rock shaft separate from the disc support for oscillating said disc, a fixed stop disposed above and cooper ating with the disc to maintain uniform depths of needle penetration, and means for changing the vertically yieldable support of the disc to a non yieldable support.

13. In a sewing machine, the combination,

with a stitch forming mechanism including a reciprocatory needle, of a slotted pressed foot, a work support, a ridge-forming disc located in the plane of the slot of the presser foot, means for yieldably supporting said.

disc on said work support for bodily vertical movements, the path of needle reciprocations being in a plane crossing the plane of the disc, means including a rock shaft separate from the disc support for oscillating said disc, said disc support including a disc-supporting roller journaled on the work support'and vertically movable relative thereto, I

and means mounted on the work support for yieldably supporting said roller.

14 In a sewing machine, the combination with a stitch forming mechanism including a-reciprocatory needle, of a slotted presser foot, awork support, a ridge-formingv disc located in the plane of the slot of the presser foot, means for yieldably supporting said" disc on said work support for bodily vertical movements, the path of needle reciprocation's being in a planecrossing the plane of i the disc, means including a rock shaft separate from the disc support for oscillating said disc, said disc support including an arm pivoted on the worksupport, a disc-supporting roller journaled on the arm, a stop on the work support to limit the upward movement of said arm, and a spring interposed between the work support and the arm for yieldably retaining the arm against the stop.

15. In a sewing machine, the combination with a stitch forming mechanism including a reciprocatory needle, of a slotted presser foot, a work support, aridge-forming. disc located in the plane of the slot of the presser foot, means for yieldably supporting said disc on said work support for bodily vertical movements, the path of needle reciprocations being in a plane crossing the plane with a stitch forming mechanism including a reciprocatory needle, of a slotted presser foot, awork support, a'ridge-forming disc located in the plane of the'slot of the presser foot, means for yieldably supporting said disc on said work support forbodily vertical movements, the path of needle reciprocations being in a plane crossing the plane of the disc, means including a rock shaft separate from the disc support for oscillating said disc, said disc support including an arm pivoted on the work support, a disc-supporting roller journaled 011 the arm, a stop on the worksupport to limit the upward movement of said arm, a spring interposed between the work support and the arm for yieldingly retaimngthe'arm against the stop, and a vertically adjustable screw mounted on the work support for cooperation with the spring to vary the tension thereof, the screw being movable upwardly to take up the spring and to abut the roller supporting arm and thereby retain the arm against downward yielding action. i

17. In a sewing machine, the combination with a stitch forming mechanism including a reciprocatory needle, of a slotted presser foot, a work support disposed below .said

foot, a ridge-formingdisc located in theplane of the slot of the foot, means below the foot for yieldablysupporting said disc on said work support for bodily vertical movements, the path of needle reciprocations being in a plane crossing the plane of the disc, and a fixed stop mounted onthe'fo ot in front of the needle and disposed above and cooperating with the disc to maintain 1111i".

form depths of needle penetration;

18. In a sewing, machine, the combination with astitch forming mechanism including a.

reciprocatory needle, of a slotted presser foot, a work support disposed below said foot, a ridge-forming disc located in the plane of the slot of the foot, means below the foot for yieldably supporting saiddisc on said work support for bodily vertical movements, the path of needle reciprocations being in a plane crossing the plane ofthe disc, and a vertically adjustable fixed stop mounted on the foot in front of the needle and disposed above and cooperating with the disc to maintain ,uni form depths of needle penetration 19. In asewing machine, the combination with astitch forming mechanism including a reciprocatory needle, of a slotted presser foot, a work support disposed below said foot, a ridge-forming disc located in the plane of the slot of the foot, means below the foot for yieldably supportingsaid disc on said work support for bodily vertical movements, the path of needle-reciprocations being in a plane crossing the plane of the disc, a verticallyadjustable fixed stop mounted on thefoot in front of the needle and disposed above and cooperating with the disc to maintain uniform depths of needle penetration,

said stop including a stop plate extending over the disc and having its front end pivoted on a horizontal axis on .the foot, and a ver: tically adjustable stop supported on the foot and disposed above and cooperating with the plate to limit the upward movement thereof.

20. In a sewing inachine,'the combination witha stitch forming mechanism including a reciprocatoryneedle, of a slotted presser foot, a work support, a ridge-forming disc supported for oscillations on said work sup port and located in the plane of the slot in the foot, the path of needle reciprocations being in a plane crossing the plane of the disc, means for imparting forward and backward oscillating movements to the disc and for imparting anv upward bodily movement and a downward bodily movement to the disc during the respective oscillating movements thereof, and means for yieldably supporting said disc during said upward and downward movements thereof.

21. In a sewing machine, the combination with a stitch forming mechanism including a reciprocatory needle, of a slotted presser foot, a work support, a ridge-forming disc supported for oscillations on said work support and located in the plane of the slot in the foot, the path of needle reciprocations being in a plane crossing the plane of the disc, means for imparting forward and backward oscillating movements to the disc and for imparting an upward bodily movement and a downward bodily movement to the disc during the respective oscillating movements thereof, means for yieldably supporting said disc during said upward and downward V movements thereof, and a fixed stop disposed and a downward bodily movement to the disc during the respective oscillating movements thereof, means for yieldably supporting said disc during said upward and downward movements thereof,and a vertically adjustable fixed stop disposed above and cooperating with said disc.

- 23. In a sewing machine, the combination with a stitch forming mechanism including a reciprocatory needle, of a slotted presser foot, a work support, a ridge-forming disc supportedfor oscillations on said work support and located in the plane of the slot in the foot, the path of needle reciprocations eases being in a plane crossing the plane ofthe disc, said disc support includlng a per1ph eral cam on the lower edge of the disc, a

roller journaled on the work support andin 1 direct contact with the disc, means for oscillating said disc whereby the same will be bodily raised and lowered through said cam and roller during the respective forward and backward oscillating movements thereof, and means for yieldably supporting said roller during the upward and downward movements V of the disc.

24. In a sewing machine, the comb nation with a stitch forming mechanism including a reciprocatory-needle, of a slotted presser foot, a work support, a ridge forming disc supported for oscillations on said work support and located in the plane of the slot in the foot, the path of needle reciprocations being in a plane crossing-the plane of the disc,

said disc support including a peripheral cam' onthe lower edge of the disc, a roller journaled on the work support and in direct contact with the disc, means for oscillating said disc whereby the same will be bodily raised and lowered through said cam and roller during the respective forward and backward oscillating movements thereof, means for yieldably supporting said roller during the upward and downward movements of the disc, and a fixed stop disposed above and cooperating with said disc.

25. In a sewing machine, the combination with'a stitch forming mechanism including a reciprocatory needle, of a slotted presser foot, a work support, a ridge-forming disc supported for oscillations on said work support and located in the plane of the slot in the foot, the path of needle reciprocations being in a planecrossing the plane of the disc, said disc support including a peripheral cam on the lower edge of the disc, a roller journaled sci on the work support andin direct contact with the disc, means for oscillating'said disc whereby the same will be bodily raised and lowered through said cam and rollerduring the respective forward and backward oscillating movements thereof, means for yieldably supporting said roller during the upward and downward movements of the disc, and a vertically adjustable fixed stop disposed above and cooperating with said disc. r

26. Infa sewing machine, the combination with a stitch forming mechanism including a reciprocatory needle, of a slotted presser foot, a work support, aridge forming disc supported for oscillations on said work support and located in the plane of' the slot in the foot, the path of needle reciprocations being in a plane crossing the plane of the disc, said disc support including a peripheral cam on the lower edge of the disc, a roller journaled on the work support and in direct'contact with the disc, an arm pivotally connected the work support, means for oscillating said disc whereby the same will be bodily raised and lowered through said cam and roller during the respective forward and backward oscillating movements thereof, and stop means connected to the disc supportingarm and cooperable with the work support to limit the upward movement of the disc.

In testimony whereof I hereunto affix my signature.

CHARLES W. MUELLER. 

